1. Field of the Invention
This invention relates to fittings for drawing fuel from fuel tanks through apertures provided for fuel level sensors.
2. Description of Related Art
Diesel engine heaters are used to keep diesel engines warm when they are turned off to facilitate restarting. Such heaters reduce the need to keep vehicle engines running, particularly during cold weather, thus reducing polluting emissions from idling engines and the accompanying noise pollution.
Diesel engine heaters of this type conventionally burn diesel engine fuel obtained from the fuel tank of the vehicle. Often this means drilling a special hole in the fuel tank to receive a special fitting so the fuel line from the heater can be inserted into the tank. This is often undesirable, particularly if the diesel engine heaters are to be installed as original equipment. Manufacturers of vehicles are hesitant to drill additional holes in fuel tanks because this lessens the structural integrity of the tank itself and possibility increases the risk of tank failure and consequent legal liability. In addition, drilling additional holes in tanks is prohibited for certain vehicles such as buses in some jurisdictions.
Consequently, there is a need to provide means for installing fuel lines for diesel engine heaters without requiring additional apertures to be drilled in the fuel tanks. One possibility is utilizing the apertures already in place for fuel level sensors for most vehicles. Devices for removing fuel via fuel level measuring devices have been developed in the past. An example is found in U.S. Pat. No. 4,939,932 to Ritzonthaler where fuel can be removed through a suction tube. A special level measuring device is required though to remove fuel from the tank.
In U.S. Pat. No. 4,557,144 to Lucchini, a level sensor for motor vehicle tanks includes a fuel withdrawal line which passes through a special flange. Like the previous patent, this device is not well adapted for retrofitting existing tanks while utilizing existing, standard fuel level measuring devices.